1. Field of the Invention
The present invention relates to power conservation. Specifically, the present invention relates to a method and apparatus for deactivating a clock to floating point circuitry, for example, in a processor or a computer system, when floating point operations are not required.
2. Background Information
Power conservation is increasingly becoming a concern in both computer system and processor design. Due to the proliferation of portable or so-called "laptop" computers, environmental concerns, and other design considerations, almost uniformly, designers are seeking more and more opportunities to reduce power consumption by both processors and computer systems.
Prior art solutions to power consumption problems have included the release of processors which operate at lower power levels. Other solutions have included modes which deactivate system power to components in a computer system when not in use. For example, if a fixed-media or hard-disk drive in not accessed for a certain period of time, the drive may be spun down. If a system remains idle, its monitor may be dimmed or its processor may be put to "sleep." In yet other prior art solutions, the entire system may be put to "sleep" (e.g. deactivated) if there is inactivity for a predetermined time period. Myriad other solutions have been and are being developed which address these needs.
One feature provided in state of the art processors is the availability of floating point operations. In early designs, because of processor design complexity, such features were provided via a separate co-processor (e.g. the Intel brand Intel287.TM. and Intel387.TM. co-processors available from Intel Corporation of Santa Clara, Calif.), which was only installed in a computer system if the user desired. In modern processors, such as the Intel486.TM. (except for the Intel 486SX) and Pentium.RTM. brand processors available from Intel (Intel287, Intel387, Intel486, Intel 486SX and Pentium are trademarks of Intel Corporation), such floating-point functionality has been provided in the main processor.
Many applications do not use floating point operations on a regular basis. Notwithstanding, modern processors such as these continue to clock the floating point circuitry, even though no floating point operations are being executed or floating point registers are in use. Although power-saving versions of these processors continue to be developed and made available, prior art solutions to reduce power consumption have been lacking, especially due to the unnecessary operation of certain circuitry in a processor or co-processor in a computer system.
Thus, the prior art of power conservation, in processor and computer system design, suffers from deficiencies.